This invention relates generally to kneaded marine paste products, called suisan-neri-seihin in Japan, also referred to as "surimi-based products" by the Food and Drug Administration of the U.S. Government, particularly marine paste products made from ground fish paste, called suri-mi in Japan. More particularly, this invention relates to a method of heating marine paste products to coagulate their proteins.
Marine paste products such as various fish paste products such as kamaboko and chikuwa (fish paste cakes, tubes, patties, balls, etc.) are produced by methods involving heating. Such heating may be conducted only once in some cases for the purpose of converting the raw state of fish after molding to an edible state, or twice with or without alteration of temperature, time, etc. in other cases. Also in the case of production of the so-called imitation "crab leg" kamaboko, heating is generally conducted twice. That is, the first heating is generally called the preliminary heating, which is applied to the product in the form of sheets or fibrous product cut into pieces therefrom. Then the heated product is molded into a rod-shaped product, packed in a certain amount into a bag and subjected to the second heating to be brought into an edible state.
The purpose of heating of fish paste products is to coagulate the fish meat proteins, and therefore special care is required in carrying out the heating. More specifically, in the first place, since fish paste products will foam when heated to 100.degree. C. or higher, excessive heating must be avoided. In particular, this phenomenon is markedly observed in fish paste products in the form of sheets with engraved grooves or in fibrous fish paste products.
In addition to such care, further consideration is also necessary with respect to the point that preliminary heating of paste products is not necessarily the final step. That is to say, in some cases, paste products after preliminary heating are required to undergo post-processing steps such as application of burnt marks or molding of sheet-shaped products into rod-shaped products. In such cases, the paste products to be subjected to the post-processing steps should be free of water droplets adhering to their surfaces. (Adherence of water droplets on the surface of the product should be avoided even when the heating step is the final step without accompaniment of these post-processing steps.) However, the coagulated proteins will have low water absorbability and therefore water adhering or condensed on the surface of a paste product will inevitably exist as water droplets without being absorbed by the paste product. Accordingly, when heating is conducted by the use of conventional steam (raw vapor) as the heating source, it becomes necessary to carry out drying for a long time after heating. However, prolonged drying should be avoided, since it not only increases the probability of contamination of paste products as foods by bacteria but also prolongs unduly the time for manufacturing the paste products.